Elimination Disorders in Children

John Mersch, MD, FAAP

Dr. Mersch received his Bachelor of Arts degree from the University of California, San Diego, and prior to entering the University Of Southern California School Of Medicine, was a graduate student (attaining PhD candidate status) in Experimental Pathology at USC. He attended internship and residency at Children's Hospital Los Angeles.

David Perlstein, MD, MBA, FAAP

Dr. Perlstein received his Medical Degree from the University of Cincinnati and then completed his internship and residency in pediatrics at The New York Hospital, Cornell medical Center in New York City. After serving an additional year as Chief Pediatric Resident, he worked as a private practitioner and then was appointed Director of Ambulatory Pediatrics at St. Barnabas Hospital in the Bronx.

Elimination disorders in children facts

Constipation is defined as "a group of disorders associated with persistent,
difficult, infrequent, or seemingly incomplete defecation without evidence of a
structural or biochemical explanation."

Constipation is a relatively common
event estimated to be responsible for 3%-5% of all visits to a pediatrician's
office.

Encopresis has been defined as "the repetitive, voluntary or involuntary,
passage of stool in inappropriate places by
children 4 years of age and older,
at which time a child may be reasonably expected to have completed
toilet
training and to exercise bowel control."

Most studies indicate approximately 4%
of all children 4-17 years of age will experience encopresis.

What are elimination disorders in children?

There are two types of disorders of elimination that may affect children. One
category reflects problems with stooling, relatively common constipation and less
frequently occurring encopresis (also known a fecal incontinence or soiling).
The other category of elimination disorders in children reflects problems with
urination and is known as enuresis. The article will review only problems
associated in children dealing with stooling.
Problems with urination in
children are reviewed elsewhere.

What are the risk factors and
causes of constipation and encopresis?

Most children with encopresis have underlying constipation. Why some children
develop encopresis does not seem to reflect differences in either physiology or
psychology. Pediatric GI specialists have noted three areas of intestinal
maturation that may set the stage (in some children) for the onset of
constipation and (in some, ultimately) encopresis. These areas include the
following:

Changing from a pure breast milk/formula diet to one that includes and
ultimately relies on the majority of calories from solid foods: The increase in
solid foods promotes an increase in stool volume and consistency that may
require greater effort for stool expulsion.

The process of toilet training:
The emotional turmoil for some families in what is generally a natural
evolutionary process may engender a myriad of emotional responses in the child
who is toilet training. The often conflicting desire to please
parents but
establish autonomy may "raise the stakes" too high for the toddler to succeed.
The fact that many preschools require successfully toilet trained students may
engender parental stress since many parents utilize preschool as a safe locale
for their child during the adult's workday. One study demonstrated that 35% of
children who refused to toilet train developed chronic constipation and were at
a substantially higher likelihood of developing encopresis.

School
attendance: Pediatricians daily hear stories about children who refuse to use
the school toilet for either urinating or bowel movements. The lack of privacy,
taunting, and often noisy chaos is just too intimidating when compared with the
home environment.

Regardless of the cause, many children with constipation will ultimately pass
either an overly large and/or hard stool, resulting in a painful experience. The
rational step (from the child's perspective) is to avoid stooling and thus avoid
further pain. Consequently, stool accumulates in the rectum and becomes
desiccated and thus more difficult and more painful to pass. This recurrent
cycle reinforces the child's behavior to avoid stooling at all costs. Children
who develop encopresis may develop abnormal stretching and enlargement of the
rectal area that reduces the reflex urge to stool. As a consequence, the impacted
stool mass may allow "upstream" semisolid stool to leak around the "downstream"
stool obstruction, causing soiling in clothes as well as occasional chunks of
stool to also be passed without the child's knowledge or desire.

Causes of Bedwetting

The fundamental problem for children with primary bedwetting is the inability to recognize messages of the nervous system sent by the full bladder to the sleep arousal centers of the brain while asleep. In addition, bladder capacity is often smaller in bedwetting children than in their peers.